Clutch assembly for drawworks



April 29, 1952 s/w. LONG 2,594,666

CLUTCH ASSEMBLY FOR DRAWWORKS 15, 1949 2 SHEETS-SHEET 1 Filed April W. LONG INVENTOR.

l5 'HTTORNEY'S April 29, 1952 s. w. LONG 2,594,666

CLUTCH ASSEMBLY FOR DRAWWORKS Filed April 15, 1949 2 SHEETS-SHEET z h INVENTOR. 1 1 SPENCER w. LONG W 3% BY E W M HTTORIVEYS Patented Apr. 29, 1952 UNITED STATES PATENT OFFICE "CLUTCH ASSEMBLY FOR DRAWWORKS Spencer W. Long, Inglewood, Calif., assignor to The National Supply Company, Pittsburgh, Pa., a corporation of Pennsylvania Application April 13, 1949. Serial No. 87,249

The-principal object of my invention is to provide a new and improved form of clutch assembly for use in a rotary drawworks.

Another object is to provide a heavy-duty, high-capacity, friction clutch for a draw'works, the clutch being adapted for operation by fluid pressure, and provided with selectively operable positive drive means which is automatically re leased upon over-running of the driven. member.

Another object is to provide a clutch assembly for driving a drawworks drumshaft. the assembly having friction drive means and positive drive means, the positive drive means being employed for controlling the rate of rotation of the spooling drum in a reverse direction.

A more detailed. object is to provide a heavyduty, high-capacity, friction drive clutch assembly' for a drawworks and having releasable positive driving jaw members for establishing a positive driving connection when desired, one of. the members being self-centering on a cone sup port in its inoperative position.

Further and more detailed objects and advantageswill appear hereinafter.

In the drawings;

Figure 1 is a plan view partly in section and partly broken away showing a well drilling drawworks of the type used in connection with my invention.

Figure. 2 is a sectional view of a preferred em-" ture carried thereon, are hereinafter referred to asthe drawworks. frame I18; A spooling drum 19 provided with. the usual brake rims 20 is fixed on a drumshaft 2|. This drum shaft is supported on axially spaced bearings 22. These'bearings, as

well as: other bearings hereinafter described, are supported by elements of the frame omitted in- Figure' 1 for purposes of clarity of illustration.

A low speed drive sprocket 23 is rotatably mounted-con the drumshatt 2| and is adapted to be connected in driving relationship with the drumshaft 2| by means of the air operated frlc t. tion'clutch 24 embodyingmy invention, anddescribed hereinafter. The high speedv drive sprocket 25 is fixed on the drumshaft 2|. and is provided with jaws 26 for connection withm'ating jaws 21 on the clutch 28. The clutch 28' is splined to the brake shaft 29 for operating. the auxiliary brake 30. A line shaft 3| rotatably'sup ported in an axially spaced bearing 32 carried by the frame I8, is provided with a high-speed drive sprocket 33 rotatably mounted on the line shaft and arranged to be connected in driving relation therewith by means of an air operated friction clutch ,assembly 34. The sprocket 33 is adapted. to drive the sprocket 25 by means of the drive chain 35. A low speed drive sprocket 36 is the sprocket 23 through the drive chain 31'.

A jackshaft assembly generally designated 38 '1 includes a pair of aligned jackshaft sections 39 and 49 rotatably supported in" axially spaced bearings 41 and 42. These bearings are carried by the drawworks frame iii. A driving sprocket 43, rotatably mounted on the jacks'haft section 39, is connected by a chain 44 to drive the sprocket 45 fixed to the line shaft 3l.- Means are provided for driving the jackshaft section 39, and as shown on the drawings this means includes a powerreceiving sprocket 46 driven by a chain 41. The sprocket 46 is fixed to a sleeve 48 rotat ably mounted on the jackshaft section 39'. .Anaxially shiftable clutch 49 is provided with splined teethill on one' end and: a gear 5! onthe other end. The member 49 may be shifted to engage the splined teeth 56 with similar splined teeth (not shown) within the sleeve 48, thereby con-- nectin'g the sleeve 48 in driving relationship with the sleeve 52. The sleeve 52' is rotatably mounted on the j ackshaft section-39s A splined clutch 53 may be shifted. axially of the sleeve 52 to connect its inner splined teeth (not shown) with the splined ring 54 fixed on the sprocket 43'. Thus,. the sprocket may be driven ina forward direction. and: the splined clutch 53 engages the splined ring. 54 when the splined clutch 49 engages the sleeve 48..

A reverse drive is provided: for rotating the jackshaft section 39 in a reverse direction when required; This reverse drive includes a double sprocket 55 fixed on the sleeve 48 and connected by chain to drive the sprocket :56 fixed: on the countersha'ft'sleeve 51. The countershaft sleeve 51 is mounted on suitable bearings (not shown)" and is provided with a driving gear 58 fixedther-= on. The countershaft sleeve 5'! is constantly ro tated with the power-receiving sprocket 48, but it merely idles under normal driving conditions. When a reverse drive is required the clutch 49 is moved axially to place the gears and 58 into mesh, thereby disengaging the splined teeth 58. The sleeve 52 is then driven in a reverse direction, and upon closing of the splined clutch 53 the sprocket 43 and jackshaft section 39 are rotated in a reverse direction.

An air operated friction clutch assembly generally designated 59 is provided for connecting the adjacent ends of jackshaft sections 39 and 48. This clutch assembly 59 includes a ring 68 fixed to the jackshaft section 39 and a housing 6I fixed to the jackshaft section 48. An inflatable rubber-like ring 62 on the housing 6| carries friction shoes 63 adapted to contact the periphery of the drum 64 formed on the ring 60. From this description it will be understood that inflation of the annular ring 62 serves to effect a driving engagement whereby the jackshaft assembly 48 is driven from the jackshaft section 39. When the inflatable ring 62 is deflated the shoes 63 move out of engagement with the drum 64, with the result that the driving connection is interrupted. An inertia brake assembly 65 may be provided for holding the jackshaft section 48 from rotation when desired.

Means are provided on the jackshaft section 48 for driving a rotary machine (not shown) at a plurality of speeds. As shown in the drawings. this means includes a pair of driving sprockets 66 and 61, which are fixed on the jackshaft assembly 48. A countershaft 68 rotatably supports the axially spaced bearing 69 carrying a pair of sprockets I8 and II connected by chains 12 and .13 to be driven from sprockets 66 and 61 respectively. The driven sprockets I8 and H are rotatably mounted on the countershaft 68 and either may be connected in driving relationship with the countershaft 68 by means of the axially shiftable clutch 14. From this description it will be understood that the countershaft 68 may be driven at either of two speeds with respect to the jackshaft section 48.

A beveled gear I5 fixed on the countershaft 88 drives a similar beveled gear 16 fixed on the stub shaft 11, which is carried on bearing I8. A selfaligned coupling I9 connects one end of the power transmission shaft 88 to the stub shaft 11 and a second self-aligning coupling 8| connects the other end of the transmission shaft 88 to the power transmission shaft 82. This latter shaft 82 extends under a guard 83 and is connected to rotate the drive shaft of the rotary machine (not shown).

A catshaft 84 is rotatably connected in axially spaced bearings 85 carried on the drawworks frame I8. This catshaft may be provided with a cathead assembly 86 on each end thereof as shown in Figure 1. The catshaft is provided with a driven sprocket 81 fixed thereon arranged to be driven from driving sprocket 88 rotatably mounted on the line shaft 3|. A chain 89 connects the sprockets 81 and 88. A sprocket I fixed on the jackshaft section 39 drives the sprocket 8 which is fixed to the sprocket 88.

In conventiontal drilling rigs the cable which is wound on the spooling drum I9 is paid out gradually in order to feed the drill string and bit into the formation. This feed-off operation is accomplished conventionally by relaxing the brake bands (not shown) which are trained over the brake rims 28. The feed-off accomplished by relaxation of the brake bands is irregular and 4 intermittent, and it is known that it does not act to maintain constant feeding pressure on the drill bit.

In order to overcome this difficulty, there is provided a speed reduction unit 98 which may include a single or double worm gear reduction. The slow speed shaft 9I of this unit 98 is connected by means of sprocket 92 and chain 93 to the sprocket 94 which is rotatably mounted on one end of the line shaft 3|. A jaw clutch 95 is provided for releasably connecting the sprocket 94 in direct driving relationship with the line shaft 3|. The high speed shaft 96 on the unit 98 is connected by coupling 98 to a hydraulic motor 99. A hydraulic pump I88 is connected by coupling I8I in direct driving relationship with the jackshaft section 48. Hydraulic lines I82 and I83 connect the hydraulic motor 99 with the hydraulic pump I88 so that the pump may drive the motor. A suitable control device I84 of conventional type is operatively positioned in the lines I82 and I83 or associated with the pump I88 for regulating the volume of flow of hydraulic fluid between the pump I88 and motor 99.

From this description it wil be understood that the rotating jackshaft section 48 may drive the pump I88 which in turn drives the hydraulic motor 99. The motor 99 drives the shaft 96 at a relatively high speed, and the output shaft 9| turns at a very much slower speed. This slow speed drive is then communicated via sprockets 92, 94, 36 and 23 to turn the spooling drum I9 very slowly in a direction to pay off or to unspool the cable for feeding the drill string. The control I84 may have remote actuating mechanism positioned at the drillers control panel I if desired. -This control I84 may be set by the driller to provide a fixed rate of flow in the lines I82 and I83 so that regardless of the speed of the jackshaft section 48 the pump 99 turns the shaft 96 at a rate to produce the desired rate of feed-off rotation for the spooling drum I9.

The provisions for supplying air to each of the air operated friction clutches and for supplying cooling water for the brake rims 28 of the drum I9 are largely omitted from the drawings for purposes of clarity of illustration. Similarly, the lubricating connections, fittings, piping, etc. which convey lubricants to the various bearings of the device are also omitted from the drawings. In accordance with my invention a hub H8 is fixed on a tapered end I89 of the drumshaft 2|. A key I I I prevents relative rotation. A pla'te'I I2 is secured to the shaft end by means of cap screws I I3 and serves to hold the huh I I8 in position on the tapered shaft end. External splines H4 are provided on the outer periphery of the hub, and these splines are engaged by the internal splines formed on the inner diameter of the annular friction disks H5. A first friction plate H6 is positioned between the disks I I5 and a second friction plate H1 is positioned adjacent the stationary wall H8 of the clutch housing or shell I I9. A

I23. The piston I28 is sealed with respect to the shell and cover by means of a flexible diaphragm I24. A rotary stufiing box assembly I 25 carried by the cover I22 at a location on the center line:

pressure into the space I26 between the piston I23 and the cover I22. From this description. it will be understood that the shell I I9 is placed. in driving relationship with the hub H3 when air pressure is admitted into the space I23 to bring the friction disks II5 into engagement with the pistonv I23 and friction plates H3 and II'I- The driving sprocket 23 is connected to the shell I I9 of the clutch 22. As shown in the draw-.-

ings this connection includes a plurality of threaded elements I2! and a plurality of pins 528 which transmit the torque. Ihe driving sprocket 23. is provided with an elongated annular hub section I29 mounted on axially spaced bearings I30 and I3I. J-

In accordance with my inventicnl provide an annular clutch. ring I32 which is carried, on the sprocket member 23. ihis clutch ring |32 encircles a portion. of the elongated hub section I29 andv is provided with splines I33 on its outer periphery. These splines engage within internal splines I3 1 provided within, the bore of the cylindrical section I35 of the shell I19. Bevel clutch jaws I36 are provided on the clutch ring I32 and a companion set of bevel clutch jaws I3? are mounted on a side face of the hub IIfi. A plurality of axially extending pins I38 are attached to the clutch ring I32 at one end and are attached to a shifter collar I39 at the other end. A compression spring I43 encircles each of the pins :38.

of: the drumshaft 2| serves to introduce fluid One end of each spring engages the shifter collar I39 and the other end engages a washer I-iI fixed within the web I42 0f the sprocket member 23. It. will be understood that each of the pins I33 extends through the web Hi2. A non-rotary ring I43 may be axially shifted by any suitable fork device (not shown) to move the shifter collar I39 to the left as viewed in Figure 2. This moves the pins I38 and brings the bevel jaws I33 of the clutch ring I32 into driving engagement with the companion jaws I31 carried on the hub H3. Engagement of the jawsltfi and I3! establishes a positive driving connection between the sprocket member 23 and the drumshaft 2 I. This is a valuable feature for it enables the drumshaft 2| to be turned even in the event of failure of air supply for actuating the high capacity friction clutch 24.

The clutch ring I32 may be moved back to the inoperative position shown by applying a force to the nonrotary ring I43, if desired. The clutch ring I32 is provided with a conical bore HM which seats on the conical surface I provided on the hub section I29 of the sprocket 23. The spring I maintains the conical surfaces I24 and IE5 in engagement so that the clutch ring I32 in its inoperative position is held in a central position so that it does not vibrate or chatter and so that it does not cause wear on the interengaging splines I33 and I34.

The clutch ring I32 has an important function with the feed-01f device above described. When the drum I9 is unspooling line while the drill string is being rotated the clutch ring I32 is moved to its operative engaged position to connect the drumshaft 2| in positive driving relatlonship with the sprocket 23. During the long periods of drilling it is unnecessary to introduce air into the space I26 for clamping the friction disks II5. When it is desired to raise the drill string after an interval of drilling with the bit on bottom the air operated friction clutch 34 on the line shaft 3| is engaged to bring the high speed drive through sprocket 25 into play, thereby rotating the drum I9 in a forward direction.

to wind up the cable thereon andv thereby raise the drill string oif bottom. When the high speed:

drive through sprockets 33 and 25 rotates the drumshaft 2|, the hub IIB over-runs the clutch ring I32 with the result that the beveled surfaces I46 on the clutch ring I32 and hub I I0 automati cally disengage the jaws I36 and I3? so that the springs I40 may move the clutch I32 backto its inoperativev position. It is therefore to be under-. stood that the high speed drive through sprocket 25 may be brought into play at any time while a Having fully described my invention, it. is -toi-z' be understood that I do not wish tobe limitedto the details herein set forth, but my invention is of the. full scopeof the appended claims.

I claim:

1. In a. device of the class described, the combination of a shaft, a hub fixed on the shaft and provided with an annular series of external spline teeth, a power transmitting member rotatably mounted on the shaft and having a radial walland an axially extending shellencircling the hub, a sprocket fixed to said member, a friction diskcarried by said hub within said shell and having internal splines cooperating with the spline teeth on the hub, a movable element carried on the:

member and adapted to clamp the friction disk.

between the element and said radial wall where-- by. a friction driving connection is established between the member and the hub, fluid pressure means for actuating said element, mechanical means for effecting a positive driving engagement between said member and the hub, said means including an axially slidable clutch ring splined on said member, cooperating conical surfaces on the clutch ring and said member forming a seat for the clutch ring in its inoperative position, and cooperating bevel clutch jaws on the clutch ring and hub adapted to be engaged through axial movement of the clutch ring, the bevel jaws being disengaged when the hub overruns the power-transmitting member.

2. In a device of the class described, the combination of a shaft, a hub fixed on the shaft and provided with an annular series of external spline teeth, a power transmitting member rotatably mounted on the shaft and having a radial wall and an axially extending shell encircling the hub, a sprocket fixed to said member, a friction disk carried by said hub within said shell and having internal splines cooperating with the spline teeth on the hub, a movable element carried on the member and adapted to clamp the friction disk between the element and said radial Wall whereby a friction driving connection is established between the member and the hub, fluid pressure means for actuating said element, mechanical means for effecting a positive driving engagement between said member and the hub, said means including an axially slidable clutch ring splined on said member, cooperating conical surfaces on the clutch ring and said member forming a seat for the clutch ring in its inoperative position, resilient means acting to move the clutch ring toward said seat, and cooperating bevel clutch jaws on the clutch ring and. hub

adapted to be engaged through axial movement of the clutch ring, the bevel jaws being disengaged when the hub overruns the power-trans: mitting member.

3. In a device of the class described, having ashaft rotatably mounted upon spaced bearings on one of said members and splined torotate therewith, axially engageable bevel jaws on the clutch ring and the other member whereby the clutch ring may drive the member and whereby overrunning of the member with respect to the clutch ring automatically moves the clutch ring axially to disengage the jaws, cooperating conical surfaces on the clutch ring and said member forming a seat for the clutch ring in its disengaged position, alpair of friction disks encircling the hub member and each splined to one of said members, and fluid actuated means adapted to bring said disks into frictional engagement with each other to establish a frictional driving connection between said members.

4. In a device of the class described, having a shaft rotatably mounted upon spaced bearings and an overhanging end of the shaft extending beyond one of the bearings, the combination of a hub member fixed on the overhanging portion of the shaft, a pair of spaced roller bearings supported on said shaft between the hub member 4 and the shaft bearing, a power-transmitting member mounted on said spaced roller bearings for rotation relative to the shaft, releasable mechanical means for effecting a positive driving engagement between said members, said means including an axially slidable clutch ring carried on one of said members and splined. to rotate therewith, axially engageable bevel jaws on the clutch ring and the other member whereby the clutch ring may drive the member and whereby overrunning of the member with respect to the clutch ring automatically moves the clutch ring axially to disengage the jaws, cooperating conical surfaces on the clutch ring and said member forming a seat for the clutch ring in its disengaged position, a pair of friction disks encirclin the hub member and each splined to one of said members, means adapted to bring said disks into frictional engagement with each other to establish a frictional driving connection between said members, said means including a fluid actuated piston supported by the power-transmitting member and encompassing the end of the shaft.

SPENCER W. LONG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 18,947 Greve Sept. 12, 1933 1,794,613 Heany Mar. 3, 1931 2,161,075 Morgan June 6, 1939 2,360,489 Gillett Oct. 17. 1944 

